Portable devices such as a cellular telephone, a game machine, and a personal computer, for example, are popular. Although limitations are imposed on the sizes of the displays of these devices because the devices are portable, users demand a large screen as large as possible. Therefore, there is a device in which a terminal is foldably configured and the size of the display is secured. Among such devices, there is a device configured in which one part is a display and the other part is a manipulation member such as buttons when the device is opened.
A device mounted with a touch panel is also popular. The touch panel is often integrally formed on a display and configured to manipulate icons, for example, displayed on the display. There is also a portable terminal including such a touch panel. Patent Document 1 describes a cellular telephone including a touch panel. When a touch panel is applied to a cellular telephone, a possibility arises that the touch panel contacts the ear to cause a malfunction in making a call, for example. Patent Document 1 describes that such malfunctions are prevented using an acceleration sensor.